Interrogating the function of motile ciliated cells in spinal curvature using a zebrafish model of adolescent idiopathic scoliosis

总结 青少年特发性脊柱侧凸（AIS）是一种普遍的发育状况（影响约3%的 人群），其特征为发生异常的三维脊柱弯曲， 在青少年成长的各个阶段。最近，许多斑马鱼模型的AIS已经成为强大的 用于解决疾病病因学和表征基本生物学机制的工具， 促进脊柱伸直。然而，这些模型的不同遗传基础， 脊柱弯曲和生长脊柱的复杂性-为脊柱的组织提供界面的组织 骨骼，肌肉和神经系统-意味着进行定量，表型分析的能力， 微计算机断层扫描（microCT）数据是我们描述 调节和维持脊柱的平直度。本提案的目的是消除这一障碍， 通过将定量、多尺度表型组学分析的新模式应用于AIS的斑马鱼模型， 这将使我们能够解决有关发展机制的基本问题， 保持脊柱平直。 我的导师最近的研究表明，突变的斑马鱼在运动过程中会麻痹运动的纤毛， 幼年生长的窗口发育出再现AIS的三维脊柱弯曲。我们的中央 假设椎管室管膜的运动纤毛是局部神经元传导的关键信号装置。 脊柱直度和弯曲度的“感知”和机械矫正。我们打算挑战这些 通过三个具体目标的想法：（1）测试在脊柱伸直运动纤毛的空间需求。 (2)确定哪些特定的运动纤毛细胞类型对直脊柱至关重要。(3)测试以下要求 运动纤毛下游机械轴中的接触脑脊液神经元。研究设计：我们将使用 定量，多尺度表型组学平台，以评估遗传操作的影响， 纤毛运动对脊柱直度的整体、部分或细胞类型特异性失活。这将通知我们的 了解活动纤毛如何将信息传递到其局部组织环境，有助于我们的 基本了解脊柱如何“知道”直生长，并告知我们未来的发展方向， AIS的研究和治疗。

Summary Adolescent Idiopathic Scoliosis (AIS) is a prevalent developmental condition (affecting ~3% of the population) of unknown origin, characterized by abnormal, three-dimensional spinal curvatures that occur during phases of adolescent growth. Recently, numerous zebrafish models of AIS have emerged as powerful tools for addressing etiology of the condition and characterizing the fundamental biological mechanisms that facilitate spinal straightness. However, the varied genetic underpinnings of these models, the diversity of their spinal curvatures, and complexity of the growing spine – a tissue that provides an interface for tissues of the skeletal, muscular, and nervous systems – means that an ability to perform quantitative, phenotypic analysis on micro-computed tomography (microCT) data is a critical barrier to our ability to describe the pathways that mediate and maintain spinal straightness. The objectives of this proposal are to address this barrier to progress by applying a new modality of quantitative, multiscale phenomics analysis to zebrafish models of AIS, which will allow us to address fundamental questions about the developmental mechanisms that mediate and maintain spinal straightness. Recent work by my advisor has shown that zebrafish with mutations that paralyze motile cilia during windows of juvenile growth develop three-dimensional spinal curvatures recapitulating AIS. Our Central Hypothesis is that motile cilia of the spinal canal ependyma are critical signaling devices in the local `perception' and mechanical correction of spinal straightness and curvature. We intend to challenge these ideas through three Specific Aims: (1) Test the spatial requirement for motile cilia during spinal straightness. (2) Identify which specific motile ciliated cell types are critical for a straight spine. (3) Test the requirement for CSF-contacting neurons in a mechanical axis downstream of motile cilia. Research Design: We will use our quantitative, multiscale phenomics platform to evaluate the impact of genetic manipulations involving either global, partial, or cell-type specific inactivation of cilia motility on spinal straightness. This will inform our understanding of how motile cilia relay information to their local tissue environments, contribute to our fundamental understanding of how the spine “knows” to grow straight, and inform our future directions in the research and treatment of AIS.